p15*sm p17*sm 120hz and LightBoost

Hi

When I saw that the p15*sm and p17*sm barebones had a DisplayPort 1.2
I just assumed that 120hz monitors and LightBoost would be supported.
But looking at the specs more closely I see that p15*sm and p17*sm do
have a displayport 1.2 but only the VGA in p37*sm barebones
"Supports DisplayPort 1.2". So I'm starting to seriously doubt 120hz and
lightboost are possible with p15*sm and p17*sm barebones, and that would be kind
of a deal-breaker for me since I think that even "heavy" games that can't go above
60 fps or even 30 fps, benefit from 120hz refresh rate and even more from
LightBoost (because the main problem with lcd screens wrt to old crt is the
"blurring" effect during the transition from a frame to another and a 120hz
refresh rate can greatly help with that, and even more so LightBoost: for the
interested look here LightBoost HOWTO | The Blur Busters )

Anyone tried to attach a p15*sm or a p17*sm to a 120hz monitor
through displayport? (hdmi doesn't support 120hz unless it's ver 1.4b)

 

I'll add that, if indeed it isn't possible to have 120hz through displayport, the intel IGP shouldn't be the culprit this time.
With 680m+hd4000 there was a bottleneck because hd4000 didn't support displayport 1.2 (and hence 120hz) and I believe optimus always routes the data through the intel IGP (which would be the bottleneck). Now both the 780m and the HD4600 supports displayport 1.2 so at least on paper there shouldn't be any technical reason for not having 120hz through displayport. Or at least this is what I've been able to gather snooping around.

 

So, I had an answer from the techsupport of a clevo reseller which said that fullhd 120hz via displayport on an external monitor is supported by p15*sm and p17*sm. But I'm reading everywhere about this damn bottleneck imposed by optimus and I haven't been able to find one single instance where 120hz and optimus were actually working together. So I'm not sure if the tech guy knew what he was saying or if I just made such a good case for a positive answer (the hd4600 does support displayport 1.2 and fullhd@120hz so where's the bottleneck with optimus?) that I just convinced him

 

Yes, according to the iGPU 4600 specs, 120hz should be supported at 1920x1080p. As a matter of fact, even the 1.1a DP supports 120hz at 1920x1080. This is according to this document, page 18:

http://www.vesa.org/wp-content/uploads/2011/01/ICCE-Presentation-on-VESA-DisplayPort.pdf

However, like you mentioned many say that optimus/enduro would be the problem here, but every one of them fail to mention the reason why, as both iGPU and dGPU support these refreshrates+resolution.

My post is more or less redundant but it's very important(for us at least) that someone with a p15*sm or p17*sm with a 120hz screen comes forward and can conclude on this matter. This might save me 200 extra bucks for the p37*sm!

 

Googling around for "nvidia optimus" the uncertainty and doubt have grown
considerably. Apparently just plugging a 120hz fullhd monitor to DP is not
sufficient proof that you can play with it. That's because from the various horror
stories about optimus that I've gathered on forums and such we have the following:

For any given video output connection X (like DP, HDMI, VGA),
laptop manufacturers can decide if X is attached
1) to "optimus", i.e. to the iGPU with the dGPU able to access it
through the iGPU with the method we know
2) exclusively to the dGPU, and that would be awesome for me: if X=DP and they
attached the 780m directly to it there would be no hd4600 in the way
3) exclusively to the iGPU....oh yeah, that means that you attach you monitor
to X, maybe you can get fullhd 120hz if you have the hd4600 and X=DP
but the dGPU cannot access that external monitor (and you're stuck playing
crysis 3 with a beautiful 120hz fullhd monitor but with all the almighty
power of the hd4600)

Now, none of the cases I've found are about the 7xxm series (too new) but there
are cases up to the 6xxm series so I'm not really sure that things have changed
with optimus, hd4600 and 7xxm.

About clevo in particular. I can't get a convincing answer from any reseller I've
asked. There is nothing about these problems in the manual for the p15*sm and
p17*sm series. I don't know if there is any tech paper about these series where
this kind of details is treated clearly. I don't think clevo.tw techsupport
answer to final users (or prospective ones, for that matters).
So I don't know where to bang my head.

 

I have found the following from mysn.de(Clevo reseller):

They apparently have tested all the laptops with a displayport on 1920x1080 at 120hz, and according to them it works. Even with the optimus or enduro technology in it.

Source:

- mySN.de | SCHENKER XMG | Schenker Technologies
- Google translate: Google Translate
- mySN.de | SCHENKER XMG | Schenker Technologies - XMG P502 PRO Gaming Notebook 39,6cm (15.6") (Go to tab Technische Daten and then ‘Grafik’

BUT going back to your post above, it would really really REALLY suck if 120hz(under situation 3) were to work ONLY UNDER hd4600, would mean for me that the 780m becomes almost entirely redundant.

EDIT!!

I have called Schenker notebooks and they have assured me that even tho the signal goes through the HD 4600, you will still be using your dGPU while gaming under 120hz!! Thing is, it will not work with 3D or lightboost with Enduro/Optimus.

Note, they have tested this!

 

Yes yesterday I found that same faq you found and googletranslated it. And I was happy for a while
until I found out that there was the possibility of scenario 3) (although, again, it wasn't with a 7xxm but I think it
was a 6xxm coupled with hd4000). In that scenario that faq from mysn.de could just mean that you'd be happily
using a fullhd 120hz with the iGPU and the dGPU would be isolated. So the happiness didn't last long....

If I were you (you seem to be located in north america) I'd go for a p370sm (the other one is too flashy to me)
without a doubt, no optimus, no problems.....But here in EU I'm not aware of any resellers with p370sm's in their listings.

 

I didn't see your edit!

Well that's good news!

Still....lightboost...

 

Actually, I live in The Netherlands.

I know 2 ishops who offer the 370sm, xnotebooks stationed in NL(called cyclone) or mysn.eu stationed in GER(called P723). I will probably go for mysn.eu.

Hope that should determine ur choice

 

Sorry. You wrote "200 extra bucks" and I just assumed you were talking about dollars

Thanks.
I didn't know about the reseller in NL and I must have completely missed that model on mysn.eu

 

The 375sm actually gets a full blown thunderbolt port

 

Ye I have checked it out and apparently the thunderbolt is backward compatible with mini DP 1.2. To be honest, I have no need for the thunderbolt and there aren't that many products out there supporting this port yet. I think that USB 3.0 should be fine for a while, the same for DP 1.2.

375sm is a good 200 bucks more expensive for the barebone alone and it is more massive as well, so I would like to avoid spending the extra cash if the 170/177sm are able to output 120hz perfectly fine

 

The good news is that LightBoost can be tricked to work without needing 3D initialization. nVidia LightBoost is a two-step unlock (1) one-time monitor feature unlock then it's easily enabled thereafter; then (2) send it a Custom Resolution. You need to do (1) again if you unplug your computer monitor, so keep your monitor plugged in if you want to easily re-enable LightBoost.

1. Sometimes you have to connect the monitor to a different nVidia computer and "initialize" the LightBoost (e.g. with ToastyX Strobelight). Then hotplug the DVI cable / DisplayPort cable to your laptop after you set it up.

2. Then configure the laptop with a compatible mode (e.g. 1920x1080 Custom Resolution with a Vertical Total of 1149), either via ToastyX CRU, nVidia Custom Resolution, or ToastyX Strobelight

3. LightBoost should automatically activate everytime you simply switch to 120Hz, with any graphics driver (as long as it's outputting the correct custom timings).

There is an open question about the GPU performance, as LightBoost really shows benefits mainly at 120fps@120Hz -- if you can only do 60fps@120Hz, you won't get much LightBoost benefit. So you'll be wanting to play older games that are able to run at a full 120 frames per second, e.g. Quake Live

Some people have even used the hotplug trick (one-time initialization on nVidia computer to) to get LightBoost functioning on AMD (and possibly even Intel HD series).

But first, test out ToastyX Strobelight and see if it is able to initialize LightBoost computer monitor, since ToastyX Strobelight has its own built-in LightBoost initialization that bypasses the requirement for using 3D Vision drivers.

 

Sorry for stealing this topic but.... I don't care much for the 3d or lightboost all I want is 120hz(since i play quake live, which runs at 125 fps, 120hz would be GREAT). You are 100 percent sure that 120hz won't be a problem? Simply attach it with DP and switch it to 120hz at Nvidia controlpanel?

 

On the P15x and P170x it wont be the nvidia control panel, it will be the intel one.